[test] Moved all error related libraries under their own user

This allows to have a cleaner content and a dedicated place for
error related tests.

beat/core/test/test_algorithm_dependencies.py

@@ -109,7 +109,7 @@ def test_dependencies():
 def test_invalid_dependencies():
 
     name = "user/for_dep/1"
-    dep_name = "user/invalid_dep/1"
+    dep_name = "errors/invalid_dep/1"
 
     copy_objects(name, dep_name)
 
@@ -118,7 +118,7 @@ def test_invalid_dependencies():
     nose.tools.eq_(len(alg.uses), 0)
     nose.tools.eq_(len(alg.libraries), 0)
 
-    l_dep = Library(tmp_prefix, "user/invalid_dep/1")
+    l_dep = Library(tmp_prefix, "errors/invalid_dep/1")
     nose.tools.assert_true(l_dep.valid, "\n  * %s" % "\n  * ".join(l_dep.errors))
 
     alg.uses["dep"] = dep_name

beat/core/test/test_lib.py

@@ -109,7 +109,7 @@ def test_indirect_recursion():
 
 def test_invalid_mix():
 
-    lib = Library(prefix, "user/invalid_mix/1")
+    lib = Library(prefix, "errors/invalid_mix/1")
     nose.tools.assert_false(lib.valid)
     nose.tools.eq_(len(lib.errors), 1)
     nose.tools.assert_not_equal(lib.errors[0].find("differs from current language"), -1)
@@ -200,7 +200,7 @@ def test_adding_self():
 def test_invalid_dependencies():
 
     name = "user/for_dep/1"
-    dep_name = "user/invalid_dep/1"
+    dep_name = "errors/invalid_dep/1"
 
     lib = Library(prefix, name)
     nose.tools.assert_true(lib.valid, "\n  * %s" % "\n  * ".join(lib.errors))